The present invention relates to a flat knitting machine with transfer mechanism comprising a transfer jack bed (hereinafter it is referred to as xe2x80x9cTRJ bedxe2x80x9d) in which a number of transfer jacks (hereinafter they are referred to as xe2x80x9cTRJxe2x80x9d), each having a loop retaining portion at a front end thereof, are arranged in series and which is arranged over needle beds, and a transfer cam mechanism for transferring the loop between the TRJ of the TRJ bed and the knitting needles of the needle beds, and to a transfer method.
There exists a flat knitting machine comprising a pair of front and back needle beds holding knitting needles in such a manner as to be advanced and retracted in needle grooves formed on upper surfaces of the needle beds, at least one of which is racked horizontally with respect to the other needle bed, and a TRJ bed located over the at least one needle bed and holding TRJ in such a manner as to freely advance and retract in the grooves formed on an upper surface thereof. This type of flat knitting machine has the capability of transferring a loop between knitting needles of the front and back needle beds as well as between a knitting needle and TRJ, as disclosed, for example, by Japanese Laid-open (Unexamined) Patent Publication No. Hei 6(1994)-257039.
FIG. 5 illustrates the motions of the knitting needle and TRJ at each stage of transferring a loop from TRJ to a knitting needle. In this figure, 101 denotes the knitting needle, 103 denotes the TRJ, and 105 denotes the loop. FIG. 5A illustrates the state immediately prior to the course knitting, in which the TRJ 103, after having received the loop 105 from the knitting needle 101, is advanced to a position over a needle bed gap. In this advanced position of the TRJ, the loop 105 retained on a loop retaining portion 103a formed at a front end portion of the TRJ is allowed to be transferred from the JRJ to the knitting needle.
In FIG. 5B, the knitting needle 101 of the front needle bed is advanced and inserted into the loop 105 retained on the loop retaining portion 103a of the TRJ 103, to receive the loop 105. Then, as shown in FIG. 5C and FIG. 5D, the TRJ 103 is retracted from the advanced position, to release the loop 105 from the TRJ 103 and put the loop 105 on the knitting needle 101. FIG. 5E shows the state in which the transfer of the loop 105 is completed as a result of the knitting needle 101 being retracted and thereby the loop 105 being captured by a needle hook 101a of the knitting needle 101.
In some cases, when the TRJ 103 retracts from the state shown in FIG. 5C and FIG. 5D, the loop 105 is sometimes slid closer to the retracting TRJ 103, so that when the knitting needle 101 is retracted in the condition shown in FIG. 5E, the needle hook 101a sometimes fails to capture the loop 105 to produce a drop stitch 105a. There are some probable factors for the drop stitch. For example, in the case where the TRJ has some shape to hinder the loop 105 from being released smoothly from the loop retaining portion 103a, the loop 105 is easily slid closer to the TRJ when retracted. Particularly in the case where a knitting yarn of low stretch is used to knit a fabric, once the loop 103 is slid closer to the TRJ 103, the loop 105 is kept in such a deformed shape without retuning in its original shape even after the TRJ is pulled therefrom and, as a result of this, the drop stitch is produced.
To solve the drawbacks mentioned above, the present invention provides a flat knitting machine with a loop transfer mechanism comprising a pair of front and back needle beds, on which knitting needles, each comprising a needle body having a needle hook at a front end thereof and a slider movable relative to the needle body to close the needle hook, are held in such a manner as to freely advance and retract, and at least one of which is racked laterally with respect to the other needle bed, and a TRJ bed, provided over the at least one needle bed and holding TRJ in such a manner as to freely advance and retract, the flat knitting machine with the loop transfer mechanism further comprising: a needle body control portion for controlling the needle body in such a manner that when a loop retained on the TRJ is transferred to the knitting needle of a lower needle bed, the needle body can be advanced to insert the needle hook of the knitting needle into the loop held on the loop retaining portion of the TRJ; a TRJ control portion for controlling the TRJ to move forward so that the loop retained on the loop retaining portion of the TRJ can be pushed to be placed in an advancing and retracting track of the needle hook of the knitting needle; and a slider control portion for controlling the slider to move forward so that the needle hook can be closed by the slider to capture and keep in the needle hook the loop retained on the loop retaining portion of the TRJ pushed by the TRJ control portion.
Also, the present invention provides a transfer method for transferring a loop from TRJ to a knitting needle by using a flat knitting machine with a loop transfer mechanism comprising a pair of front and back needle beds, on which knitting needles, each comprising a needle body having a needle hook at a front end thereof and a slider movable relative to the needle body to close the needle hook, are held in such a manner as to freely advance and retract, and at least one of which is racked laterally with respect to the other needle bed, and a TRJ bed, provided over the at least one needle bed, for holding TRJ in such a manner as to freely advance and retract, wherein when a loop is transferred from the TRJ to the knitting needle of a lower needle bed, the needle hook of the knitting needle is inserted into the loop; then the TRJ is moved forward so that the loop retained on the TRJ can be pushed to be placed in an advancing and retracting track of the needle hook of the knitting needle; and the slider is moved forward so that the needle hook can be closed by the slider to capture and keep the loop in the needle hook.
According to the present invention, when the loop retained on the TRJ is transferred to the knitting needle of the lower needle bed, the needle body of the knitting needle on the loop receiving side is moved forward so that it can run through the loop retained on the loop retaining portion of the TRJ. Sequentially, the TRJ is moved forward by the TRJ control portion so that the loop can be pushed to be placed in the advancing and retracting track of the needle hook. With the loop held in the advancing and retracting track of the needle hook, the slider is moved forward by the slider control portion so that the needle hook can be closed by the slider. As a result of this, even when the loop is slid closer to the TRJ when sequentially retracted for completion of the transfer of loop, since the loop is captured and kept in the closed needle hook, the loop is prevented from being slipped off from the needle hook when the needle is retracted sequentially. Thus, generation of the drop stitch is prevented.